Pulp-forming press



April 5,1927.

E. HUTCHENS PULP FORMING PRESS Fi ied April 2. 1925' 2 Sheets-Sheet l v EJT'ILEIE @cfZ/Hl/Zohens April 5, 1927.

E. HUTCHENS PULP FORMING PRESS.

2' Sheets-Sheet 2 h Filed April 1925 JJ VE m :rg Edward/1U take/7o" Patented Apr. 5. 1927.

PATENT *oFFlcE.

nnwann nu'rcnnns, or MILWAUKEE, wrsoonsm.

rune-romaine rnnss.

Application filed April 2; 1926. Serial No. 99,216.

This invention relates to the manufacture of articles from paper stock or pulp.

It is an object of this invention to provide mechanism for manufacturing a variety of articles such as, for example, stool and toilet seats from chemically treated pulp made from waste paper or the like. The material itself, and the resulting product, forms no part of the present invention which relates to the apparatus used in the process of manufacturing such articles by compressing and drying or baking the pulp in suitable molds.

It is another object of this invention to provide an improved hydraulic piston having a filter plate head with water discharge and vacuum connections leading from beneath said filtering plate.

Heretofore, horizontally arranged hydraulic presms have been used'to form articles from paper pulp, but such an arrangement of the press results in an article with the lower side more dense due to settlement of the pulp in the water before and during the pressing operation. Further wire cloth or fine screens have been used as a filtering medium but have clogged at the first pressing, and from then on the water could only escape as steam or past loo'se fitting plstons. It is, therefore, an object of this mventlon to provide an improved vertical hydraul c press adapted to form the article in a hOI'lzontal' position to avoid segregation.

It is also an object of this invention to provide an improved filtering medlum having a series of parallel hair line slots adapted to permit ready cleaning by brushing lengthwise of the slots.

This invention (in a preferred form) is illustrated in the drawings and hereinafter.

' more fully described.

On the drawings:

Figure 1 is an elevation of a hydraulic press embodying the features of thelnvention.

Figure 2 is a top plan view thereof.

Figure 3 is a section on the line III-III of Figure 1 showing the pistonhead in plan view.

Figure 4 is a section on the line IV--IV' of Figure 3 showing the piston passage.

Figure 5 is anenlarged plan view of the filtering plate with the width of' theslots greatly exaggerated.

Figure 6 is a top plan view of the' piston with the filtering plate removed.

Figure 7 is a fragmentary section of the filtering plate,taken on the line VIL-VII of Figure 5.

As shown on the drawings;

A vertical hydraulic press is shown com; prising a top head 10, cored at 11' for a steam pocket supplied by the pipe 12. Thihead is tied to a. base 13 by rods 14, the base having the usual hydraulic cylin- Ccr bore 15 with a hydraulic ram16 therein, with a suitable packing gland 17 surrounding the ram. The operating fluid is supplied through a pipe 18 and check valve 19 to a lever operated pump 20 supported on a bracket 21, the pump discharging through a check valve 22 to'the inlet 23 to the by draulic cylinder 15, by suitable piping 24 includlng a pressure gauge 25 and release valve 26, In commercial use the press would probably be operated directly from a high pressure fluid supply line but a hand pump has been illustrated to complete the showing.

A press cylinder 28 is suspended from the top head 10 and contains a removable form or die 29 therein conforming to the V shape of the article to be produced. Below the die a stock inlet .port 30 has a stock plunger valve body 31 and pipe connection 32 molmted thereon, the valve plunger 33, lever 34, and lock screw 35 being indicated. An.air' vent is also provided from the'cylinder 28, a lever plug 36 therefor together with a locking bracket'37' being shown in Figure 1.

The press piston is of special construction and is bolted on top of the ram by the flange 38, the enlarged piston section 39 making a close fit in thefpress cylinder 28. The form of the cylinder die, and piston section of course varies with the article to be produced, a plain circular form being shown such as is suitable for the production of stool seats. The top.of the'piston proper is provided with a series of interconnected concentric ring grooves 40'communicating with a central cored passage 41 having across passage 42 with connections at both ends, one adapted tocreate a vacuum in the ring grooves and the-other for drainage purposes. Suit,-

able flexible hose may be used for the con tapered so that any material entering the slot will easily pass completely through and thereby avoid clogging the filter. Further, the use of parallel slots instead of woven screens permits ready cleaning by using a bristle brush in the direction of the slots. the bristles of a brush readily entering and removing material therefrom.

The piston head is also provided with cored passages 45 for steam heating the piston.

In the operation of this machine the piston is raised into the cylinder to a height necessary to make the final product the right thickness. the pulp stock averaging several times as much water-as fibre. The pulp valve and air vent are then opened and the space in the cylinder between the die and pi:ton top completely filled with pulp, whereupon the pulp valve and air vent are closed.

The steam supply is maintained constant to the top head of the hydraulic press and in the piston head also if desirable for the article to be made.

Upon applying further fluid pressure to the ram it rises and the water in the pulp is forced through the filter plate slots and drained away. A vacuum is then created beneath the filter plate, or alternatively, a

vacuum may be also used during the initial draining period. It is, however, more economical to allow the major part to drain away before applyinglthe vacuum, which then serves to draw off t e steam generated in the compressed pulp by the heat.- ing from the steam jackets or cored passages. The use of a vacuum at this stage accelerates the baking or drying operation and prevents sogging of the product.

of the water It will thus be seen that I have produced an improved and simplified mechanism for producing articles from compressed paper pulp.

I am aware that many changes may be made, and numerous details of construction may be varied through a wide range without departing from the principles of this invention, and I therefore do not purpose limiting the patent granted hereon, otherwise than necessitated by the prior art.

I claim as my invention:

1. In combination with a hydraulic press a cylinder a form therein, a piston adapted to enter the cylinder, a series of connected grooves in the top surface of said piston, a slotted filter plate secured above said grooves, and a connection from said grooves to a source of sub-atmospheric pressure.

2. In combination with a hydraulic press a cylinder a form therein, a piston adapted to enter the cylinder, a series of connected grooves in the top surface of said piston, cored steam passages in said piston, a slotted filter plate secured above said grooves, and a connection from said grooves to a source of sub-atmospheric pressure.

3. In combination with a hydraulic press a cylinder, steam compartments in the head of said press, a form therein, a piston adapted to enter the cylinder, a series of connected ooves in the top surface of said piston, a slotted filter plate a secured above said grooves, and a connection from said grooves to a source of sub-atmospheric pressure.

In testimony whereof I have hereunto subscribed my name.

EDWARD HUTCHENS. 

